Effects of Rotating Back-propagation Pressure Wave on Centrifugal Compressor Operation

Abstract Research has shown that rotating detonation turbine engines have the potential to enhance aero-engine performance. However, the rotating back-propagation pressure wave (RBPW) generated by the detonation-based combustor can adversely affect the upstream compressor. In this study, this unsteady backpressure was simulated using a user-defined function (UDF), and its impact on a centrifugal compressor was numerically investigated. The results show that, under single-wave RBPW, both the total pressure ratio and isentropic efficiency declined at the same mass flow rate compared to steady-state conditions. Variations in the characteristic parameters of the RBPW resulted in shifts of the compressor's operating point. A higher-pressure distortion index caused a greater deviation from the original characteristic line. Increasing the propagation frequency or using a multi-wave configuration mitigated these adverse effects. Under four-wave excitation, compressor performance exceeded that of steady operation. Finally, the stability boundaries of the compressor under RBPW were defined in terms of constant flow rate and constant power constraints.